Agroindustrial wastes as a substrate for the cultivation of Eruca sativa Miller seedlings: physical-chemical and phytometric parameters assessment.

Evaluation was made of the use of organic substrates obtained from the composting of poultry industry wastes, together with crude glycerin, for the production of arugula seedlings (Eruca sativa Miller). The raw materials included hatchery waste, chicken litter, and flotation tank sludge, in combination with other materials such as tree pruning, sugarcane bagasse, crude glycerin (at 0, 1.5, 3.0, 4.5, and 6.0%), and boiler charcoal. Analysis of the organic substrates included determination of nitrogen, phosphorus, and potassium (NPK), pH, electrical conductivity, functional groups, and carboxylic acids. Physical parameters determined were water retention capacity, solids volume, porosity, density, and granulometry. For the arugula seedlings, determinations were made of the ease of removal of the root ball from the tray, the effect of free drop on the root ball, phytometric parameters, and total phenolic compounds. Decreased concentrations of carboxylic acids, together with the presence of aromatic functional groups, indicated maturation/stabilization of the organic substrates. The phytometric measurements indicated that the use of the organic substrates with addition of 3.0, 4.5, and 6.0% of crude glycerin favored arugula production and led to higher contents of total phenolic compounds in the seedlings, with values of 3657.54, 3602.13, and 3232.92 mg GAE g-1, respectively. The results demonstrated that the use of these organic substrates with the addition of crude glycerin provided satisfactory development of arugula seedlings.

Composting of swine production chain wastes with addition of crude glycerin: organic matter degradation kinetics, functional groups, and carboxylic acids.

Little is known about the effect of adding crude glycerin (CG) as a carbon source during the composting of agro-industrial residues, such as those generated in the swine production chain, especially concerning the impact on organic matter humification. Therefore, the aim of this work was to study the effect of adding crude glycerin during the composting of organic swine waste, using appropriate analyses to determine the degree of maturation of the organic material. The experiment was performed using composters constructed from pallets. The variables considered were temperature, mass, volume, organic matter, functional groups, carboxylic acids, pH, electrical conductivity, total organic carbon, total Kjeldahl nitrogen, total phosphorus, potassium, basal respiration, and germination index. For all the CG concentrations tested, thermophilic temperatures were reached, while higher amounts of CG (4.5 and 6.0%) maintained temperatures above 55 °C for longer periods (28 days). Fourier transform infrared spectroscopy analysis showed the presence of an aromatic stretching vibration signal at 1620 cm-1, confirming mineralization of the organic matter, while the decrease of carboxylic acids at the end of the composting period indicated stabilization. The organic composts presented high nutrient contents and absence of toxicity, indicating that they could be safely used in agriculture.

Zero valent iron mediated degradation of the pharmaceutical diazepam.

Parameters that influence the zero valent iron mediated degradation of the pharmaceutical diazepam (DZP) were evaluated including the iron concentration and its pre-treatment, the effect of complexation with EDTA and oxic versus anoxic condition. It was observed that acid pre-treatment of iron particles is important for degradation efficiency and that H(2)SO(4) is a better choice than HCl, resulting in higher degradation of DZP. Under oxic conditions, the degradation of DZP achieved 96% after 60 min using Fe(0) (25 g L(-1)) pre-treated with H(2)SO(4) in the presence of EDTA (119 mg L(-1)), while mineralization achieved around 60% after the same time. Under anoxic conditions, degradation occurred, however at lower extent, achieving 67% after 120 min. The addition of EDTA improved the treatment efficiency in 20% leading to 99% DZP degradation after 120 min. The first intermediates formed during DZP degradation were identified using LC/MS analysis and revealed the formation of mono- and di-hydroxylated products from DZP during Fe(0)/EDTA/O(2) degradation, which evidences that (·)OH was the main oxidizing species formed in this process.